Research On Section Monitoring System Based On Power Line Carrier Communication

China's railway have been speeding up six times,the train speed is faster and faster,the operation time interval is shorter and shorter,increase the ability of railway transportation.This has played a great role in promoting the development of China's national economy.The increase of train speed depends more and more on section signaling equipment.The normal operation of a section signaling device is especially important,but in view of the impact of money and technology on the design of the system,there are too few monitoring of outdoor equipment such as signal and track circuit.According to statistics,most of the signal equipment failures occur outdoors,while the centralized monitoring system is a signal collected indoors,which can not reflect the real use of the signal equipment in the outdoor.When the outdoor signal equipment fails,the telecommunication personnel only to find fault through artificial methods,the fault processing time is longer,seriously affected the traffic.Based on this,this paper puts forward the scheme of monitoring system for section signaling equipment.The monitoring system consists of many outdoor trackside monitoring units and an indoor interface machine.Monitoring the lighting state of the section signal,the current voltage at the side of the cable of the section signal and the side of the lamp at the end of the section signal,the current voltage and code status at the cable side and track side of the section track circuit by the wayside monitoring unit,then the monitored information is transmitted back to the indoor interface machine via wired or wireless means,the indoor interface machine displays the monitoring information in the room and uploads the information to the centralized monitoring system,the centralized monitoring system completes the inspection and alarm analysis of the monitoring information of the section signal equipment.Considering the power supply and communication lines do not need to rewire,which means we can directly use the existing cable as data transmission and power supply channels,and use cable core as little as possible to reduce site construction work,therefore,the communication mode between trackside monitoring unit and indoor interface machine is power line carrier communication.Firstly,this paper analyzes the characteristics of power line channel,and chooses IT700 carrier chip which is suitable for Chinese power line channel through the comparison of carrier chip at home and abroad.Then the section monitoring system and power line carrier communication system based on IT700 carrier chip are designed in detail.Finally,the transmission distance and bit error rate of the power line carrier communication are analyzed by setting up the hardware circuit of the power line carrier communication system,the experiment shows that the power line carrier communication system based on IT700 carrier chip can guarantee the reliable transmission of the data collected by the section signal monitoring system.